aoc: prevent out of range on find_ramdump_section when coredump is corrupt, the value of num_sections from ramdump_header may larger than the number of sections. Out of range access will cause the KP. Bug: 302929196 Change-Id: I423886cb8223617d84cf1b21231a914c70a30dd2 Signed-off-by: yixuanjiang <[email protected]>